He wasn’t wrong. All of Caro’s book deal with the mechanics of influence and how power is used and abused and gained and lost. After studying them, you have a firm grasp of how people are manipulated. Of how things get done in a bureaucracy. Of how politics and organisations are tightly and infinitely linked. Of how incentives move the world.

John Boyd created energy manoeuvrability theory, which redefined how fighter planes were built and piloted. He wrought change within the typically conservative and bumbling Pentagon, and he introduced a theory of conflict which completely altered how the Marines operated. He called it the OODA loop.

As he was studying the history of strategy and warfare, Boyd focused on four themes: “general theories of war, the blitzkrieg, guerrilla warfare, and the use of deception by great commanders.” And he also read Sun Tzu’s The Art of War. Robert Coram describes the impact it made on Boyd:

“The Art of War became Boyd’s Rosetta stone, the work he returned to again and again. It is the only theoretical book on war that Boyd did not find fundamentally flawed. He eventually owned seven translations, each with long passages underlined and with copious marginalia.”

I have my own copy of The Art of War. Below I’ve included some of my favourite passages and why they matter two thousand years later.

“The important thing in a military operation is victory, not persistence.”

To continue down a road that holds no rewards is not heroic. Don’t be afraid to cease your efforts and re-distribute your energy down a more useful and profitable path.

“In ancient times skillful warriors first made themselves invincible and then watched for vulnerability in their opponents.”

Remove dependencies. Lower your downside. Need less. By doing that, you make it easier to invite and seize upon opportunities that arise.

“Therefore those who skillfully move opponents make formations that opponents are sure to follow, give what opponents are sure to take. They move opponents with the prospect of gain, waiting for them in ambush.”

Everyone moves out of self-interest. If you want someone to do something, you must find a way to make it beneficial for them.

“Therefore good warriors cause others to come to them, and do not go to others.”

The good and the skilled take a disproportionate share of the spoils. High expertise and authenticity are rare. If you can develop them, you will be in demand.

“Everyone knows the form by which I am victorious, but no one knows the form by which I ensure victory.”

Looking back it is easy to untangle and see clearly. Taking action now, means trying to penetrate through the fog. The former is easy. The latter takes skill and luck and courage.

“So a military force has no constant formation, water has no constant shape: the ability to gain victory by changing and adapting according to the opponent is called genius.”

In your lifetime, you will have to change many times. You will have different careers and different jobs in different places. Your ability to consistently reinvent is a big determinant in your survival.

“So morning energy is keen, midday energy slumps, evening energy recedes—therefore those skilled in the use of arms avoid the keen energy and strike the slumping and receding. These are those who master energy.”

“So the rule of military operations is not to count on opponents not coming, but to rely on having ways of dealing with them; not to count on opponents not attacking, but to rely on having what cannot be attacked.”

“Look upon your soldiers as you do infants, and they willingly go into deep valleys with you; look upon your soldiers as beloved children, and they willingly die with you.”

The ability to care sincerely for the individuals on your team matters more than any management strategy you’ll ever learn.

“If you are so nice to them that you cannot employ them, so kind to them that you cannot command them, so casual with them that you cannot establish order, they are like spoiled children, useless.”

But to care for someone, you must be strong. You must be able to say no, have uncomfortable conversations and call them out when they do wrong.

“The business of the general is quiet and secret, fair and orderly.”

Any attention you receive is often more a distraction than an advantage. Stay grounded. Keep quiet. Do the work.

“Confront them with annihilation, and they will then survive; plunge them into a deadly situation, and they will then live. When people fall into danger, they are then able to strive for victory.”

Death ground and deadlines you implement will do more for productivity than any app or lifehack.

“A government should not mobilize an army out of anger, military leaders should not provoke war out of wrath. Act when it is beneficial, desist if it is not. Anger can revert to joy, wrath can revert to delight, but a nation destroyed cannot be restored to existence, and the dead cannot be restored to life.”

The reason The Art of War still resonates today is simple. It’s about war. It’s about conflict. It’s about dealing with opposition and uncertainty and risk. These are issues we face every single day of our lives. We have to deal with people. We have to work with others. We have to choose where to place our time and attention and energy.

Ancient warriors may seem like unlikely candidates for inspiration and guidance, but they’re not. They were remarkably similar to us. They were human. So are we. Which means we can learn from them.